3.3.2 Use a strong, one-way cryptographic algorithm, based on approved standards to render all payment application passwords unreadable during storage. Each password must have a unique input variable that is concatenated with the password before the cryptographic algorithm is applied.

Concatenating a unique input variable to each password before the hashing algorithm is applied reduces the effectiveness of brute force attacks. Examples of strong one-way cryptographic algorithms suitable for hashing passwords include PBKDF2 and Bcrypt.